AICAR and metformin, but not exercise, increase muscle glucose transport through AMPK-, ERK-, and PDK1-dependent activation of atypical PKC

Activators of 5'-AMP-activated protein kinase (AMPK) 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR), metformin, and exercise activate atypical protein kinase C (aPKC) and ERK and stimulate glucose transport in muscle by uncertain mechanisms. Here, in cultured L6 myotubes: AICAR- and metformin-induced activation of AMPK was required for activation of aPKC and ERK; aPKC activation involved and required phosphoinositide-dependent kinase 1 (PDK1) phosphorylation of Thr410-PKC-zeta; aPKC Thr410 phosphorylation and activation also required MEK1-dependent ERK; and glucose transport effects of AICAR and metformin were inhibited by expression of dominant-negative AMPK, kinase-inactive PDK1, MEK1 inhibitors, kinase-inactive PKC-zeta, and RNA interference (RNAi)-mediated knockdown of PKC-zeta. In mice, muscle-specific aPKC (PKC-lambda) depletion by conditional gene targeting impaired AICAR-stimulated glucose disposal and stimulatory effects of both AICAR and metformin on 2-deoxyglucose/glucose uptake in muscle in vivo and AICAR stimulation of 2-[(3)H]deoxyglucose uptake in isolated extensor digitorum longus muscle; however, AMPK activation was unimpaired. In marked contrast to AICAR and metformin, treadmill exercise-induced stimulation of 2-deoxyglucose/glucose uptake was not inhibited in aPKC-knockout mice. Finally, in intact rodents, AICAR and metformin activated aPKC in muscle, but not in liver, despite activating AMPK in both tissues. The findings demonstrate that in muscle AICAR and metformin activate aPKC via sequential activation of AMPK, ERK, and PDK1 and the AMPK/ERK/PDK1/aPKC pathway is required for metformin- and AICAR-stimulated increases in glucose transport. On the other hand, although aPKC is activated by treadmill exercise, this activation is not required for exercise-induced increases in glucose transport, and therefore may be a redundant mechanism.

Disabling c-Myc in childhood medulloblastoma and atypical teratoid/rhabdoid tumor cells by the potent G-quadruplex interactive agent S2T1-6OTD

We investigated here the effects of S2T1-6OTD, a novel telomestatin derivative that is synthesized to target G-quadruplex-forming DNA sequences, on a representative panel of human medulloblastoma (MB) and atypical teratoid/rhabdoid (AT/RT) childhood brain cancer cell lines. S2T1-6OTD proved to be a potent c-Myc inhibitor through its high-affinity physical interaction with the G-quadruplex structure in the c-Myc promoter. Treatment with S2T1-6OTD reduced the mRNA and protein expressions of c-Myc and hTERT, which is transcriptionally regulated by c-Myc, and decreased the activities of both genes. In remarkable contrast to control cells, short-term (72-hour) treatment with S2T1-6OTD resulted in a dose- and time-dependent antiproliferative effect in all MB and AT/RT brain tumor cell lines tested (IC(50), 0.25-0.39 micromol/L). Under conditions where inhibition of both proliferation and c-Myc activity was observed, S2T1-6OTD treatment decreased the protein expression of the cell cycle activator cyclin-dependent kinase 2 and induced cell cycle arrest. Long-term treatment (5 weeks) with nontoxic concentrations of S2T1-6OTD resulted in a time-dependent (mainly c-Myc-dependent) telomere shortening. This was accompanied by cell growth arrest starting on day 28 followed by cell senescence and induction of apoptosis on day 35 in all of the five cell lines investigated. On in vivo animal testing, S2T1-6OTD may well represent a novel therapeutic strategy for childhood brain tumors.

Eculizumab in atypical hemolytic uremic syndrome: long-term clinical course and histological findings

Atypical hemolytic uremic syndrome (aHUS) is a thrombotic microangiopathy associated with defective regulation of the alternative complement pathway. The prognosis for patients with aHUS is poor, and plasma exchange represents the first-line therapy. Eculizumab is a humanized monoclonal anti-C5 antibody that prevents the activation of the terminal complement pathway. Here, we report the case of a 9-year-old girl with frequent relapsing aHUS due to heterozygous factor H mutation who was initially treated with plasma exchange three times per week with 150% plasma exchange volume. This treatment frequently caused allergic reactions and school absences. Because any reduction in the frequency of plasma exchange immediately induced relapses of the aHUS, treatment with eculizumab, 600 mg every 2 weeks, was started and plasma exchange completely stopped. On this drug regimen the patient showed no evidence of disease activity during a period of more than 24 months. Renal function improved, proteinuria disappeared, the number of antihypertensive medications could be decreased, and the quality of life increased substantially. The inhibition of the terminal complement pathway by eculizumab was also confirmed by renal biopsy, which showed the absence of thrombotic microangiopathy 2 months after the initiation of eculizumab therapy. This case illustrates the long-term favorable outcome of aHUS with eculizumab treatment.

Atypical presentation of a hormonally active adrenocortical tumor in an adolescent leading to delayed diagnosis

Adrenocortical tumors are rare in children and present with variable signs depending on the type of hormone excess. We herein describe the unusual presentation of a child with adrenocortical tumor and introduce the concept of in vitro chemosensitivity testing. CASE REPORT: A 10.5-year-old girl presented with hypertrichosis/hirsutism and weight loss. The weight loss and behavioral problems, associated with halted puberty and growth, led to the initial diagnosis of anorexia nervosa. However, subsequent weight gain but persisting arrest in growth and puberty and the appearance of central fat distribution prompted further evaluation. RESULTS AND FOLLOW-UP: 24h-urine free cortisol was elevated. Morning plasma ACTH was undetectable, while cortisol was elevated and circadian rhythmicity was absent. Thus a hormonally active adrenal cortical tumor (ACT) was suspected. On magnetic resonance imaging (MRI) a unilateral, encapsulated tumor was found which was subsequently removed surgically. Tissue was investigated histologically and for chemosensitivity in primary cell cultures. Although there were some risk factors for malignancy, the tumor was found to be a typical adenoma. Despite this histology, tumor cells survived in culture and were sensitive to cisplatin in combination with gemcitabine or paclitaxel. At surgery, the patient was started on hydrocortisone replacement which was unsuccessfully tapered over 3 months. Full recovery of the hypothalamus-pituitary-adrenal axis occurred only after 3 years. CONCLUSIONS: The diagnosis of a hormonally active adrenocortical tumor is often delayed because of atypical presentation. Cortisol replacement following unilateral tumor excision is mandatory and may be required for months or years. Individualized chemosensitivity studies carried out on primary cultures established from the tumor tissue itself may provide a tool in evaluating the effectiveness of chemotherapeutic drugs in the event that the adrenocortical tumor may prove to be carcinoma.

Deletions of 11q22.3-q25 are associated with atypical lung carcinoids and poor clinical outcome

Carcinoids are slow-growing neuroendocrine tumors that, in the lung, can be subclassified as typical (TC) or atypical (AC). To identify genetic alterations that improve the prediction of prognosis, we investigated 34 carcinoid tumors of the lung (18 TCs, 15 ACs, and 1 unclassified) by using array comparative genomic hybridization (array CGH) on 3700 genomic bacterial artificial chromosome arrays (resolution ?1 Mb). When comparing ACs with TCs, the data revealed: i) a significant difference in the average number of chromosome arms altered (9.6 versus 4.2, respectively; P = 0.036), with one subgroup of five ACs having more than 15 chromosome arms altered; ii) chromosomal changes in 30% of ACs or more with additions at 9q (?1 Mb) and losses at 1p, 2q, 10q, and 11q; and iii) 11q deletions in 8 of 15 ACs versus 1 of 18 TCs (P = 0.004), which was confirmed via fluorescence in situ hybridization. The four critical regions of interest in 45% ACs or more comprised 11q14.1, 11q22.1-q22.3, 11q22.3-q23.2, and 11q24.2-q25, all telomeric of MEN1 at 11q13. Results were correlated with patient clinical data and long-term follow-up. Thus, there is a strong association of 11q22.3-q25 loss with poorer prognosis, alone or in combination with absence of 9q34.11 alterations (P = 0.0022 and P = 0.00026, respectively).

Atypical presentation of Behçet's disease with central nervous system involvement successfully treated with infliximab

Central nervous system involvement is a rare and serious complication of Behçet's disease (BD). Herein, we describe a patient with an atypical central lesion, who experienced progressive hypesthesia of the right arm and sensory loss of the trigeminal nerve together with intense headache. A repeated biopsy was necessary to conclusively establish the diagnosis of BD. Therapy with infusions of infliximab led to a remarkable full remission. TNFα-blocking therapy was successfully replaced by azathioprine. The present well-illustrated case demonstrates the difficulty of establishing the diagnosis of BD with central nervous system involvement, the dramatic benefit of short given TNF-α-blocking agent, and the long-term remission with azathioprin.

Atypical scrapie isolates involve a uniform prion species with a complex molecular signature

The pathobiology of atypical scrapie, a prion disease affecting sheep and goats, is still poorly understood. In a previous study, we demonstrated that atypical scrapie affecting small ruminants in Switzerland differs in the neuroanatomical distribution of the pathological prion protein (PrP(d)). To investigate whether these differences depend on host-related vs. pathogen-related factors, we transmitted atypical scrapie to transgenic mice over-expressing the ovine prion protein (tg338). The clinical, neuropathological, and molecular phenotype of tg338 mice is similar between mice carrying the Swiss atypical scrapie isolates and the Nor98, an atypical scrapie isolate from Norway. Together with published data, our results suggest that atypical scrapie is caused by a uniform type of prion, and that the observed phenotypic differences in small ruminants are likely host-dependant. Strikingly, by using a refined SDS-PAGE technique, we established that the prominent proteinase K-resistant prion protein fragment in atypical scrapie consists of two separate, unglycosylated peptides with molecular masses of roughly 5 and 8 kDa. These findings show similarities to those for other prion diseases in animals and humans, and lay the groundwork for future comparative research.

Atypical transmissible spongiform encephalopathies in ruminants: a challenge for disease surveillance and control

Since 1987, when bovine spongiform encephalopathy (BSE) emerged as a novel disease in cattle, enormous efforts were undertaken to monitor and control the disease in ruminants worldwide. The driving force was its high economic impact, which resulted from trade restrictions and the loss of consumer confidence in beef products, the latter because BSE turned out to be a fatal zoonosis, causing variant Creutzfeldt-Jakob disease in human beings. The ban on meat and bone meal in livestock feed and the removal of specified risk materials from the food chain were the main measures to successfully prevent infection in cattle and to protect human beings from BSE exposure. However, although BSE is now under control, previously unknown, so-called atypical transmissible spongiform encephalopathies (TSEs) in cattle and small ruminants have been identified by enhanced disease surveillance. This report briefly reviews and summarizes the current level of knowledge on the spectrum of TSEs in cattle and small ruminants and addresses the question of the extent to which such atypical TSEs have an effect on disease surveillance and control strategies.

Differential pattern and prognostic significance of CD4+, FOXP3+ and IL-17+ tumor infiltrating lymphocytes in ductal and lobular breast cancers

Background Clinical relevance of tumor infiltrating lymphocytes (TILs) in breast cancer is controversial. Here, we used a tumor microarray including a large series of ductal and lobular breast cancers with long term follow up data, to analyze clinical impact of TIL expressing specific phenotypes and distribution of TILs within different tumor compartments and in different histological subtypes. Methods A tissue microarray (TMA) including 894 ductal and 164 lobular breast cancers was stained with antibodies recognizing CD4, FOXP3, and IL-17 by standard immunohistochemical techniques. Lymphocyte counts were correlated with clinico-pathological parameters and survival. Results CD4+ lymphocytes were more prevalent than FOXP3+ TILs whereas IL-17+ TILs were rare. Increased numbers of total CD4+ and FOXP3+ TIL were observed in ductal, as compared with lobular carcinomas. High grade (G3) and estrogen receptor (ER) negative ductal carcinomas displayed significantly (p < 0.001) higher CD4+ and FOXP3+ lymphocyte infiltration while her2/neu over-expression in ductal carcinomas was significantly (p < 0.001) associated with higher FOXP3+ TIL counts. In contrast, lymphocyte infiltration was not linked to any clinico-pathological parameters in lobular cancers. In univariate but not in multivariate analysis CD4+ infiltration was associated with significantly shorter survival in patients bearing ductal, but not lobular cancers. However, a FOXP3+/CD4+ ratio > 1 was associated with improved overall survival even in multivariate analysis (p = 0.033). Conclusions Ductal and lobular breast cancers appear to be infiltrated by different lymphocyte subpopulations. In ductal cancers increased CD4+ and FOXP3+ TIL numbers are associated with more aggressive tumor features. In survival analysis, absolute numbers of TILs do not represent major prognostic indicators in ductal and lobular breast cancer. Remarkably however, a ratio > 1 of total FOXP3+/CD4+ TILs in ductal carcinoma appears to represent an independent favorable prognostic factor.

Atypical findings in delayed presentation of unilateral acute idiopathic maculopathy

Unilateral acute idiopathic maculopathy is a rare disease affecting young healthy patients resulting in moderate to severe unilateral visual loss preceded by prodromal flu-like illness. We present a case of delayed presentation of unilateral acute idiopathic maculopathy associated with hand, foot and mouth disease.

European outbreak of atypical myopathy in the autumn 2009

BACKGROUND: Atypical myopathy is an acute, severe rhabdomyolysis occurring in grazing horses. In the beginning of October 2009, a new outbreak occurred in several European countries. Geographic, demographic and clinical data of the reported cases in the month October 2009 are described. KEY FINDINGS: The survival rate in this outbreak was 25%. The most frequently observed clinical signs were congested mucous membranes, dyspnea, tachycardia, depression, weakness, stiffness, recumbency, trembling, sweating, and myoglobinuria. Nonsurvivors were significantly more likely to be recumbent than survivors. Prognostic factors, symptomatic treatment, and preventive measures are discussed. SIGNIFICANCE: Differences were encountered during the described outbreak of atypical myopathy in October 2009 compared with previous outbreaks reported. Equine practitioners should be aware that previous epidemiological studies have shown that after a high prevalence in the autumn, new cases are likely to occur in the following spring.

Atypical depression and alcohol misuse are related to the cardiovascular risk in the general population

OBJECTIVE: The aims of the present study were to assess the associations between mood, anxiety and substance use disorders, including their subtypes, and the prevalence of cardiovascular risk factors (CVRFs). METHOD: Thorough physical investigations, biological measures and standardized interview techniques were used to assess 3716 subjects of an urban area, aged 35-66 years. RESULTS: Atypical depression was associated with increased prevalence of overweight, diabetes and the metabolic syndrome (OR = 1.5, 95% C.I. 1.1-2.0; OR = 2.0, 95% C.I. 1.1-3.5, OR = 1.6, 95% C.I. 1.0-2.4 respectively), whereas decreased prevalence of overweight was found in melancholic (OR = 0.7, 95% C.I. 0.6-0.9) and unspecified depression (OR = 0.8, 95% C.I. 0.7-1.0). Alcohol abuse was associated with diabetes (OR = 1.8, 95% C.I. 1.1-2.9) and dyslipidemia (OR = 1.3, 95% C.I. 1.0-1.8), alcohol dependence with dyslipidemia only (OR = 1.4, 95% C.I. 1.0-2.0). Almost all mental disorders were associated with a lifetime history of regular cigarette smoking, and atypical depression, alcohol misuse and drug dependence were associated with inactivity. CONCLUSION: To conclude results emphasize the need to subtype depression and to pay particular attention to the atypical subtype. Comorbid alcohol misuse may further increase the cardiovascular risk. Efforts to diminish smoking in subjects with mental disorders could be crucial measures to reduce their high incidence of cardiovascular disease.